Astronomers Discover Low-Density ‘Super-Puff’ Planets

Astronomers have revealed a pair of giant planets that are less dense than cotton candy and as large as Jupiter. These planets, located 1,110 light-years away, are the least dense exoplanets of such size discovered so far. George Dransfield from the University of Oxford explained that these planets have densities similar to shaving foam.

Dransfield speculates that these wispy worlds may appear white or blue, depending on their cloud cover. Composed primarily of hydrogen and helium, confirming their chemical composition will require future observations by NASA’s Webb Space Telescope. Detected over the past decade by NASA’s Tess satellite, these planets orbit a star in the southern constellation Volans.

Researchers used Earth-based telescopes to study the planets’ orbits and determine their density. A light-year measures nearly 6 trillion miles or 9.7 trillion kilometers, illustrating the vast distance from Earth to these planets. Compared to Jupiter, which is up to 35 times denser, these planets are rare in the universe.

Super-puff planets typically form around a newborn star’s gas and dust disk, where gas predominates over dust. Over time, they lose much of their material. NASA’s current count of known exoplanets is nearly 6,300, with fewer than 40 identified as super-puffs. Dransfield emphasized that studying these rare systems helps advance understanding of planet formation and Earth’s place in the universe.

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